package test.eight;
import static util.Util.*;

class Actor{
	public void act(){}
}
class HappyActor extends Actor{
	public void act(){print("HappyActor");}
}
class SadActor extends Actor{
	public void act(){print("SadActor");}
}

class Stage{
	private Actor actor=new HappyActor();
	public void change(){actor=new SadActor();}
	public void performPlay(){actor.act();}
	
}

public class Transmogrify {
	public static void main(String[] args) {
		Stage stage=new Stage();
		stage.performPlay();
		stage.change();
		stage.performPlay();
	}
	
}
